Do Unreal FMOD Components Release Themselves When Finished Playing?

[dshodge]

I haven’t been able to find a clear answer to this question, so I’m hoping to get some clarity. If I play an FMOD component in Unreal, will the event automatically be released when it finishes playing, or do I need to manually release it? In my use case, I’m typically not stopping the event manually, and I don’t think I can release the event immediately after playing, because I need to adjust parameters later. These are non-streaming music events, so they are relatively large, and I want to ensure that they’re getting released.

[_MaX]

I could potentially test the case if you can’t figure it out. In my situation, I’m mostly in cases where anything loaded is used over and over again so release is not necessary on the blueprints who have static components inside of them.

Several things for sure :

• You have the “release” node in blueprint which has a component as the parameter
• You have the “release” flag on the “Event instance Stop” node in blueprint

Which probably implies that unless you specify (with the bool in the stop node) or control the release of the component manually… it won’t be released.

[li_fmod]

Hi,

Thank you for sharing the information!

@dshodge

If I play an FMOD component in Unreal, will the event automatically be released when it finishes playing, or do I need to manually release it?

If you use one-shot Blueprint nodes like Play Event 2D or Play Event at Location, the event instance will be automatically released once playback finishes.

However, if you’re keeping an FMODAudioComponent or an EventInstance around (e.g. to tweak parameters), it won’t be released automatically. You’ll need to either destroy the component or manually call Release() in Blueprints or via code.

In other words, if you call Play on a persistent component and never stop or destroy it, the event instance will stay in memory so you’ll need to manually release it when you’re done.

Hope this helps! Let me know if you have any questions.

[dshodge]

Thank you that is very helpful, just to follow up. This is an FMOD component that is persistent through all levels of the game and will never be destroyed, however the event will be set to a different event pretty often. Not sure if that would cause the old event to be released? In any case, there’s enough time between the event stopping annd the new event being set that I’ll want to manually release it any way. You mentioned if we don’t stop or destroy the component. Does that mean that stopping the component will release it, or does it need to be released as well? My assumption is that it needs to be released, but just want to be certain. Along those same lines, if I stop the event in a command instrument at the end of the timeline for that same event, would it be released? Again, my assumption is no, but just want to double check. I could see a use case for a command instrument option for “stop and release” or something similar.

[li_fmod]

Thank you for the extra info!

@dshodge

This is an FMOD component that is persistent through all levels of the game and will never be destroyed, however the event will be set to a different event pretty often. Not sure if that would cause the old event to be released?

No, not automatically.

If the previous event is still playing, or if it hasn’t been manually released, setting a new event on the same component will stop the old one, but it won’t release the previous event instance unless you explicitly do so.

So yes, you should manually call Release() after stopping the old event, before or after setting the new one to avoid memory buildup.

@dshodge

You mentioned if we don’t stop or destroy the component. Does that mean that stopping the component will release it, or does it need to be released as well?

Apologies for the confusion earlier.

Your assumption is correct:
Calling Stop() only stops playback, but does not release the event instance.

To fully clean it up, you’ll need to call both Stop() and Release() .

@dshodge

Along those same lines, if I stop the event in a command instrument at the end of the timeline for that same event, would it be released?

Again, your assumption is correct!

Stopping the event with a command instrument will only stop playback, but won’t release the instance.

So yes, you’ll still need to release it manually afterward to free the memory.

As a side note:
If you’re working with event instances directly, you could also store a reference and use Event Instance Stop , which gives you control over whether to release it after stopping. That can be useful if you’re managing the instance lifetime outside of the component system.

[dshodge]

Great, good to know. Just one last question, I can release the event at any time after Play() has been called, right? My thought is that the last time I set a parameter for that event I can release it and then just let it finish playing, without ever needing to stop it manually.

[li_fmod]

@dshodge

I can release the event at any time after Play() has been called, right?

Theoretically yes, you can call Release() after Play() while the event is still playing, and FMOD will mark it for cleanup once playback ends.

However, please note that:

• As soon as you call Release(), you lose control of the event instance, which means you won’t be able to set parameters or stop it manually anymore.
• In rare cases (like under heavy system load), the instance might be cleaned up before it finishes playing.

So it’s not recommended unless you’re absolutely sure the event should just finish naturally and never be touched again.

The safest pattern is to wait until the event finishes playing (e.g. using an On Event Stopped callback), then call Release() to fully clean it up.